kernel-ark/drivers/scsi/ibmvscsi/ibmvscsi.h
James Bottomley 4dddbc26c3 [SCSI] ibmvscsi: handle large scatter/gather lists
The maximum size of a scatter-gather list that the current IBM VSCSI
Client can handle is 10.  This patch adds large scatter-gather support
to the client so that it is capable of handling up to SG_ALL(255)
number of requests in the scatter-gather list.

Signed-off-by: Linda Xie <lxie@us.ibm.com>
Acked by: Dave C Boutcher <sleddog@us.ibm.com>

Rejections fixed up and
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2005-09-06 17:11:54 -05:00

112 lines
3.4 KiB
C

/* ------------------------------------------------------------
* ibmvscsi.h
* (C) Copyright IBM Corporation 1994, 2003
* Authors: Colin DeVilbiss (devilbis@us.ibm.com)
* Santiago Leon (santil@us.ibm.com)
* Dave Boutcher (sleddog@us.ibm.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* ------------------------------------------------------------
* Emulation of a SCSI host adapter for Virtual I/O devices
*
* This driver allows the Linux SCSI peripheral drivers to directly
* access devices in the hosting partition, either on an iSeries
* hypervisor system or a converged hypervisor system.
*/
#ifndef IBMVSCSI_H
#define IBMVSCSI_H
#include <linux/types.h>
#include <linux/list.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include "viosrp.h"
struct scsi_cmnd;
struct Scsi_Host;
/* Number of indirect bufs...the list of these has to fit in the
* additional data of the srp_cmd struct along with the indirect
* descriptor
*/
#define MAX_INDIRECT_BUFS 10
/* ------------------------------------------------------------
* Data Structures
*/
/* an RPA command/response transport queue */
struct crq_queue {
struct viosrp_crq *msgs;
int size, cur;
dma_addr_t msg_token;
spinlock_t lock;
};
/* a unit of work for the hosting partition */
struct srp_event_struct {
union viosrp_iu *xfer_iu;
struct scsi_cmnd *cmnd;
struct list_head list;
void (*done) (struct srp_event_struct *);
struct viosrp_crq crq;
struct ibmvscsi_host_data *hostdata;
atomic_t free;
union viosrp_iu iu;
void (*cmnd_done) (struct scsi_cmnd *);
struct completion comp;
union viosrp_iu *sync_srp;
struct memory_descriptor *ext_list;
dma_addr_t ext_list_token;
};
/* a pool of event structs for use */
struct event_pool {
struct srp_event_struct *events;
u32 size;
int next;
union viosrp_iu *iu_storage;
dma_addr_t iu_token;
};
/* all driver data associated with a host adapter */
struct ibmvscsi_host_data {
atomic_t request_limit;
struct device *dev;
struct event_pool pool;
struct crq_queue queue;
struct tasklet_struct srp_task;
struct list_head sent;
struct Scsi_Host *host;
struct mad_adapter_info_data madapter_info;
};
/* routines for managing a command/response queue */
int ibmvscsi_init_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests);
void ibmvscsi_release_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata,
int max_requests);
void ibmvscsi_reset_crq_queue(struct crq_queue *queue,
struct ibmvscsi_host_data *hostdata);
void ibmvscsi_handle_crq(struct viosrp_crq *crq,
struct ibmvscsi_host_data *hostdata);
int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
u64 word1, u64 word2);
#endif /* IBMVSCSI_H */